Reaction: Release of an N-terminal tripeptide from a polypeptide, but also has endopeptidase activity.
Other name(s): tripeptidyl aminopeptidase; tripeptidyl peptidase
Comments: A lysosomal enzyme that is active at acidic pH. Deficient in classical late-infantile neuronal ceroid lipofuscinosis brain tissue. Belongs in peptidase family S53. Formerly included in EC 18.104.22.168.
Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 151662-36-1
1. Ezaki, J., Tanida, I., Kanehagi, N. and Kominami, E. A lysosomal proteinase, the late infantile neuronal ceroid lipofuscinosis gene (CLN2) product, is essential for degradation of a hydrophobic protein, the subunit c of ATP synthase. J. Neurochem. 72 (1999) 2573-2582. [PMID: 10349869]
2. Rawlings, N.D. and Barrett, A.J. Tripeptidyl-peptidase I is apparently the CLN2 protein absent in classical late-infantile neuronal ceroid lipofuscinosis. Biochim. Biophys. Acta 1429 (1999) 496-500. [PMID: 9989235]
3. Ezaki, J., Takeda-Ezaki, M., Oda, K. and Kominami, E. Characterization of endopeptidase activity of tripeptidyl peptidase-I/CLN2 protein which is deficient in classical late infantile neuronal ceroid lipofuscinosis. Biochem. Biophys. Res. Commun. 268 (2000) 904-908. [PMID: 10679303]
4. Junaid, M.A., Wu, G.X. and Pullarkat, R.K. Purification and characterization of bovine brain lysosomal pepstatin-insensitive proteinase, the gene product deficient in the human late-infantile neuronal ceroid lipofuscinosis. J. Neurochem. 74 (2000) 287-294. [PMID: 10617131]
5. Lin, L., Sohar, I., Lackland, H. and Lobel, P. The human CLN2 protein/tripeptidyl-peptidase I is a serine protease that autoactivates at acidic pH. J. Biol. Chem. 276 (2001) 2249-2255. [PMID: 11054422]